There has been known a device for detecting linear device values distributed in a matrix. Patent Literature 1, for example, discloses a touch sensor device (contact detecting device) for detecting distribution of capacitance values of a capacitance matrix Cij (i=1, . . . , M and j=1, . . . , L) formed between M drive lines and L sense lines. The touch sensor device operates in accordance with a scanning detection method; specifically, the touch sensor device sequentially selects one of the drive lines and thus detects respective values of linear devices connected to the drive line selected.
Patent Literature 2 discloses a capacitance detecting circuit which (i) in driving a plurality of drive lines, switches between a first drive line group and a second drive line group on the basis of a time series code sequence, (ii) outputs a measured voltage obtained by converting, into an electric signal, a sum total of respective currents across capacitances, connected to sense lines, at a plurality of intersections of driven drive lines with the sense lines, and (iii) performs a product-sum operation of such a measured voltage and the code sequence for each sense line so as to find a voltage value corresponding to a capacitance at each intersection.
The description below deals with an arrangement of vertical electrodes and horizontal electrodes in a conventional capacitive touch sensor panel. FIG. 41 is a diagram illustrating an arrangement of vertical electrodes 91 and horizontal electrodes 92 in a conventional capacitive touch sensor panel. FIG. 41 corresponds to FIG. 3 of Patent Literature 1.
This conventional capacitive touch sensor panel disclosed in Patent Literature 1 includes (i) a plurality of vertical electrodes 91 provided on a vertical electrode surface and arranged at predetermined intervals in a horizontal direction and (ii) a plurality of horizontal electrodes 92 provided on a horizontal electrode surface, which is parallel to the vertical electrode surface, and arranged at predetermined intervals in a vertical direction.
Each vertical electrode 91 includes a sequence of a repeat of diamond-shaped quadrangular sections 93 and 94 connected to each other in the vertical direction. Each horizontal electrode 92 includes a sequence of a repeat of diamond-shaped quadrangular sections 95 and 96 connected to each other in the horizontal direction.
The vertical electrodes 91 and the horizontal electrodes 92, each including diamond-shaped sections, are so provided that the vertical electrodes 91 cross the horizontal electrodes 92 to constitute a capacitive touch sensor panel. In the case where such a capacitive touch sensor panel is to be placed on a display device for use, the vertical electrodes 91 and the horizontal electrodes 92 are normally each formed of a transparent conductive film made of, for example, ITO (indium tin oxide). Recent years have also witnessed research on the use of graphene as a substitute for ITO.
In the case where the diamond-shaped sections as illustrated in FIG. 41 are made of, for example, ITO and arranged on a plane, each diamond-shaped section, having both center-line symmetry and center-point symmetry, exhibits a similarly symmetric capacitance change when touched by an object, such as a pen, that has a small touch area. Utilizing this symmetry in a capacitance change allows a symmetric position correction to be carried out during a touch-position detection, and thus increases the position detection precision.
FIG. 42 is a diagram illustrating an arrangement of vertical electrodes 81 and horizontal electrodes 82 in another conventional capacitive touch sensor panel, which is disclosed in Patent Literature 2. Both the vertical electrodes and the horizontal electrodes 82 are arranged at predetermined intervals. The vertical electrodes 81 extend in a direction orthogonal to the direction in which the horizontal electrodes 82 extend. The vertical electrodes 81 and the horizontal electrodes 82 are arranged in the shape of a grid. The vertical electrodes 81 and horizontal electrodes 82 themselves individually include fine wires, which form a mesh.
(a) of FIG. 43 is a diagram illustrating an arrangement of vertical electrodes 71 in yet another conventional capacitive touch sensor panel, which is disclosed in Patent Literature 3. (b) of FIG. 43 is a diagram illustrating an arrangement of horizontal electrodes 72 in that capacitive touch sensor panel.
(a) of FIG. 43 illustrates an array of vertical electrodes 71 each including sections that each have a shape similar to a diamond shape and that are connected to one another in a vertical direction. (b) of FIG. 43 similarly illustrates an array of horizontal electrodes 72 each including sections that each have a shape similar to a diamond shape and that are connected to one another in a horizontal direction.
(a) of FIG. 45 is a diagram illustrating an arrangement of vertical electrodes in still another conventional capacitive touch sensor panel, which is disclosed in Patent Literature 4. (b) of FIG. 45 is a diagram illustrating an arrangement of horizontal electrodes in that capacitive touch sensor panel.
The capacitive touch sensor panel disclosed in Patent Literature 4 is a capacitance-type touch panel switch including (i) an electrically conductive X pattern group 61 including a plurality of conductive X sequences 62 arranged at slight intervals in the X direction and (ii) an electrically conductive Y pattern group 66 including a plurality of conductive Y sequences 67 arranged at slight intervals in the Y direction.
Each conductive X sequence 62 includes (i) a plurality of conductive X pads 63 that each have a substantially rhombic outline and that are arranged in the Y-axis direction and (ii) conductive X pads 63a that each have a substantially isosceles-triangular outline and that are arranged in the Y-axis direction to sandwich the conductive X pads 63. Adjacent conductive X pads 63 and 63 are connected to each other by a conductive X line 64, while adjacent conductive X pads 63 and 63a are also connected to each other by a conductive X line 64.
The conductive X pads 63 and 63a each include a mesh of (i) fine wires extending in the X direction and (ii) fine wires extending in the Y direction. Each conductive X line 64 is thin and includes three straight lines 65 extending in the Y direction and arranged at predetermined intervals in the X direction.
Each conductive Y sequence 67 includes (i) a plurality of conductive Y pads 68 that each have a substantially rhombic outline and that are arranged in the X-axis direction and (ii) conductive Y pads 68a that each have a substantially isosceles-triangular outline and that are arranged in the X-axis direction to sandwich the conductive Y pads 68. Adjacent conductive Y pads 68 and 68 are connected to each other by a conductive Y line 69, while adjacent conductive Y pads 68 and 68a are also connected to each other by a conductive Y line 69.
The conductive Y pads 68 and 68a each include a mesh of (i) fine wires extending in the X direction and (ii) fine wires extending in the Y direction. Each conductive Y line 69 is thin and includes three straight lines 60 extending in the X direction and arranged at predetermined intervals in the Y direction.
The X pattern group 61 and Y pattern group 66 arranged as above are so placed on top of each other as to extend orthogonally to each other in a planer view. The conductive X lines 64 of the conductive X sequences 62 and the conductive Y lines 69 of the conductive Y sequences 67 are stacked on top of each other to form a light-transmitting region having a light-transmitting property substantially identical to that of the conductive X pads 63 and the conductive Y pads 68.